tsconfig.json

{
  "compilerOptions": {
    "target": "es5",
    "lib": ["dom", "dom.iterable", "esnext"],
    "allowJs": true,
    "skipLibCheck": true,
    "strict": true,
    "forceConsistentCasingInFileNames": true,
    "noEmit": true,
    "esModuleInterop": true,
    "module": "esnext",
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "isolatedModules": true,
    "jsx": "preserve",
    // "noUncheckedIndexedAccess": true, // https://stackoverflow.com/a/50647536 試したけど, ライブラリあたりのコードの修正が面倒なので false
    "baseUrl": ".", // https://nextjs.org/docs/advanced-features/module-path-aliases
    // "paths": {
    //   "dist/*": ["src/*"] // https://stackoverflow.com/questions/43281741/how-to-use-paths-in-tsconfig-json
    // },
    "plugins": [
      // https://github.com/emotion-js/emotion/issues/1037#issuecomment-571097172
      {
        "name": "typescript-styled-plugin",
        "lint": {
          "validProperties": ["label"]
        }
      }
    ],
    "jsxImportSource": "@emotion/react" // https://emotion.sh/docs/typescript#css-prop
  },
  "exclude": ["node_modules", ".next", "bk", "src/utils/xxx/**"], // exclude されていても, included な file から import されていたら, exclude されないので注意（特に, index.ts に import が残っている場合に注意）
  "include": ["next-env.d.ts", "**/*.ts", "**/*.tsx", "**/*.js"]
}